X-Git-Url: https://harrygodden.com/git/?p=vg.git;a=blobdiff_plain;f=vg_audio_dsp.h;h=4c7d85c931907f4e52b37a2c94c6543fbe469bab;hp=c973cc9a865daa8c4238e5b00ee4ad780ae71392;hb=HEAD;hpb=e6f73232f1b16af430e850646215d2c9e07dde2e

diff --git a/vg_audio_dsp.h b/vg_audio_dsp.h
index c973cc9..d74bc02 100644
--- a/vg_audio_dsp.h
+++ b/vg_audio_dsp.h
@@ -1,42 +1,27 @@
-#ifndef VG_AUDIO_DSP_H
-#define VG_AUDIO_DSP_H
+#pragma once
 
-#define VG_GAME
-#include "vg/vg.h"
+//#define VG_ECHO_LPF_BUTTERWORTH
 
-static struct vg_dsp
-{
-   float            *buffer;
-   u32               allocations;
-
-   u8               *view_texture_buffer;
-   GLuint            view_texture;
-
-   float             echo_distances[14],
-                     echo_tunings[8],
-                     reverb_wet_mix,
-                     reverb_dry_mix;
-}
-vg_dsp;
+#include "vg_platform.h"
+#include "dep/glad/glad.h"
+#include "vg_m.h"
 
-static float *dsp_allocate( u32 samples )
+struct vg_dsp
 {
-   samples = vg_align4( samples );
+   float     *buffer;
+   u32        allocations;
 
-   if( vg_dsp.allocations + samples > (1024*1024)/4 )
-      vg_fatal_error( "too much dsp" );
+   u8        *view_texture_buffer;
+   GLuint     view_texture;
 
-   float *buf = &vg_dsp.buffer[ vg_dsp.allocations ];
-   vg_dsp.allocations += samples;
+   float      echo_distances[14],
+              echo_tunings[8],
+              reverb_wet_mix,
+              reverb_dry_mix;
 
-   return buf;
+   vg_rand    rand;
 }
-
-
-/*
- * filters
- * ----------------------------------------------
- */
+extern vg_dsp;
 
 struct dsp_delay
 {
@@ -56,241 +41,27 @@ struct dsp_schroeder
    float gain;
 };
 
-static inline void dsp_read_delay( struct dsp_delay *delay, float *s )
-{
-   u32 index = delay->cur+1;
-
-   if( index >= delay->length )
-      index = 0;
-
-   *s = delay->buffer[ index ];
-}
-
-static inline void dsp_write_delay( struct dsp_delay *delay, float *s )
-{
-   u32 index = delay->cur;
-   delay->buffer[ index ] = *s;
-
-   delay->cur ++;
-
-   if( delay->cur >= delay->length )
-      delay->cur = 0;
-}
-
-static void dsp_init_delay( struct dsp_delay *delay, float length )
-{
-   delay->length = 44100.0f * length;
-   delay->cur = 0;
-   delay->buffer = dsp_allocate( delay->length );
-
-   for( int i=0; i<delay->length; i++ )
-      delay->buffer[i] = 0.0f;
-}
-
-static void dsp_update_lpf( struct dsp_lpf *lpf, float freq )
-{
-   lpf->exponent = 1.0f-expf( -(1.0f/44100.0f) * 2.0f * VG_PIf * freq );
-}
-
-static void dsp_init_lpf( struct dsp_lpf *lpf, float freq )
-{
-   lpf->buffer = dsp_allocate( 4 );
-   lpf->buffer[0] = 0.0f;
-   dsp_update_lpf( lpf, freq );
-}
-
-static inline void dsp_write_lpf( struct dsp_lpf *lpf, float *s )
-{
-   float diff = *s - lpf->buffer[0];
-   lpf->buffer[0] += diff * lpf->exponent;
-}
-
-static inline void dsp_read_lpf( struct dsp_lpf *lpf, float *s )
-{
-   *s = lpf->buffer[0];
-}
-
-static void dsp_init_schroeder( struct dsp_schroeder *sch, float length,
-                                float gain )
-{
-   dsp_init_delay( &sch->M, length );
-   sch->gain = gain;
-}
-
-static inline void dsp_process_schroeder( struct dsp_schroeder *sch,
-                                          float *input, float *output )
-{
-   float dry = *input;
-
-   float delay_output;
-   dsp_read_delay( &sch->M, &delay_output );
-
-   float feedback_attenuated = delay_output * sch->gain,
-         input_feedback_sum  = dry + feedback_attenuated;
-
-   dsp_write_delay( &sch->M, &input_feedback_sum );
-
-   *output = delay_output - input_feedback_sum*sch->gain;
-}
-
-/* temporary global design */
-static struct dsp_lpf __lpf_mud_free;
-static struct dsp_delay __echos[8];
-static struct dsp_lpf   __echos_lpf[8];
-static struct dsp_schroeder __diffusion_chain[8];
-
-static void async_vg_dsp_alloc_texture( void *payload, u32 size )
-{
-   glGenTextures( 1, &vg_dsp.view_texture );
-   glBindTexture( GL_TEXTURE_2D, vg_dsp.view_texture );
-   glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, 256, 256, 0, 
-                 GL_RGBA, GL_UNSIGNED_BYTE, vg_dsp.view_texture_buffer );
-   glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
-   glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
-}
-
-static void vg_dsp_init( void )
+struct dsp_biquad 
 {
-   vg_dsp.buffer = vg_linear_alloc( vg_mem.rtmemory, 1024*1024*1 );
-   vg_dsp.view_texture_buffer = vg_linear_alloc( vg_mem.rtmemory, 512*512 );
-
-   vg_async_call( async_vg_dsp_alloc_texture, NULL, 0 );
-
-   /* temporary global design */
-   dsp_init_lpf( &__lpf_mud_free, 125.0f );
-
-   float sizes[] = 
-         { 2.0f, 4.0f, 8.0f, 16.0f,   32.0f, 64.0f, 128.0f, 256.0f };
-
-   float reflection_variance = 0.1f;
-
-   for( int i=0; i<8; i++ ){
-      float reflection_time = ((sizes[i])/343.0f) * 1000.0f;
-
-      float var   = 1.0f + (vg_randf()*2.0f - 1.0f) * reflection_variance,
-            total = reflection_time * var;
-
-      dsp_init_delay( &__echos[i], total / 1000.0f );
-
-      float freq = vg_lerpf( 800.0f, 350.0f, sizes[i] / 256.0f );
-      dsp_init_lpf( &__echos_lpf[i], freq );
-   }
-
-   float diffusions[] = { 187.0f, 159.0f, 143.0f, 121.0f, 
-                          79.0f,  57.0f,  27.0f,  11.0f };
-
-   for( int i=0; i<8; i++ ){
-      dsp_init_schroeder( __diffusion_chain+i, diffusions[i]/1000.0f, 0.7f );
-   }
-}
-
-static void vg_dsp_process( float *stereo_in, float *stereo_out )
-{
-   float in_total = (stereo_in[0]+stereo_in[1])*0.5f;
-   float recieved = 0.0f;
-
-   for( int i=0; i<8; i++ ){
-      float echo;
-      dsp_read_delay(  __echos+i, &echo );
-      dsp_write_lpf( __echos_lpf+i, &echo );
-      dsp_read_lpf(  __echos_lpf+i, &echo );
-
-      recieved += echo * vg_dsp.echo_tunings[i]*0.98;
-   }
-
-   float diffused = recieved;
-
-   for( int i=0; i<8; i++ ){
-      dsp_process_schroeder( __diffusion_chain+i, &diffused, &diffused );
-   }
-
-   float diffuse_mix = vg_dsp.reverb_wet_mix;
-         diffuse_mix = vg_lerpf( recieved, diffused, diffuse_mix );
-   float total = in_total + diffuse_mix;
-
-   float low_mud;
-   dsp_write_lpf( &__lpf_mud_free, &total );
-   dsp_read_lpf(  &__lpf_mud_free, &low_mud );
-
-   total -= low_mud;
-
-   for( int i=0; i<8; i++ )
-      dsp_write_delay( __echos+i, &total );
-
-   stereo_out[0]  = stereo_in[0]*vg_dsp.reverb_dry_mix;
-   stereo_out[1]  = stereo_in[1]*vg_dsp.reverb_dry_mix;
-   stereo_out[0] += diffuse_mix*2.0f*vg_dsp.reverb_wet_mix;
-   stereo_out[1] += diffuse_mix*2.0f*vg_dsp.reverb_wet_mix;
-}
-
-static void dsp_update_tunings(void)
-{
-   float sizes[] = 
-         { 2.0f, 4.0f, 8.0f, 16.0f,   32.0f, 64.0f, 128.0f, 256.0f };
-   float volumes[] = 
-         { 0.2f, 0.3f, 0.5f, 0.7f,   0.8f, 0.9f, 1.0f, 1.0f };
-
-   float avg_distance = 0.0f;
-
-   for( int i=0; i<8; i++ )
-      vg_dsp.echo_tunings[i] = 0.5f;
-
-   for( int j=0; j<14; j++ ){
-      float d = vg_dsp.echo_distances[j];
-      
-      for( int i=0; i<7; i++ ){
-         if( d < sizes[i+1] ){
-            float range = sizes[i+1]-sizes[i];
-            float t = vg_clampf( (d - sizes[i])/range, 0.0f, 1.0f );
-
-            vg_dsp.echo_tunings[i  ] += 1.0f-t;
-            vg_dsp.echo_tunings[i+1] += t;
-
-            break;
-         }
-      }
-
-      avg_distance += d;
-   }
-   avg_distance /= 14.0f;
-   
-
-   vg_dsp.reverb_wet_mix =1.0f-vg_clampf((avg_distance-30.0f)/200.0f,0.0f,1.0f);
-   vg_dsp.reverb_dry_mix =1.0f-vg_dsp.reverb_wet_mix*0.4f;
-
-   float total = 0.0f;
-   for( int i=0; i<8; i++ )
-      total += vg_dsp.echo_tunings[i];
-
-   if( total > 0.0f ){
-      float inverse = 1.0f/total;
-
-      for( int i=0;i<8; i++ ){
-         vg_dsp.echo_tunings[i] *= inverse;
-      }
-   }
-
-   for( int i=0; i<8; i++ ){
-      float freq = vg_lerpf( 200.0f, 500.0f, vg_dsp.echo_tunings[i] );
-      dsp_update_lpf( &__echos_lpf[i], freq );
-   }
-
-   for( int i=0;i<8; i++ ){
-      vg_dsp.echo_tunings[i] *= volumes[i];
-   }
-}
-
-static void vg_dsp_free( void )
-{
-   glDeleteTextures( 1, &vg_dsp.view_texture );
-}
-
-static void vg_dsp_update_texture( void )
-{
-   for( int i=0; i<512*512; i++ ){
-      float v = vg_clampf( vg_dsp.buffer[i] * 0.5f + 0.5f, 0.0f, 1.0f );
-      vg_dsp.view_texture_buffer[i] = v * 255.0f;
-   }
-}
+   f32 a0, a1, a2, b1, b2, c0, d0,
+       xnz1, xnz2, ynz1, ynz2, offset;
+};
 
-#endif /* VG_AUDIO_DSP_H */
+void vg_dsp_init( void );
+void vg_dsp_free( void );
+void dsp_update_tunings(void);
+void vg_dsp_process( float *stereo_in, float *stereo_out );
+void vg_dsp_update_texture( void );
+
+f32 dsp_biquad_process( struct dsp_biquad *bq, f32 xn );
+void dsp_init_biquad_butterworth_lpf( struct dsp_biquad *bq, f32 fc );
+void dsp_read_delay( struct dsp_delay *delay, float *s, u32 t );
+void dsp_write_delay( struct dsp_delay *delay, float *s );
+void dsp_init_delay( struct dsp_delay *delay, float length );
+void dsp_update_lpf( struct dsp_lpf *lpf, float freq );
+void dsp_init_lpf( struct dsp_lpf *lpf, float freq );
+void dsp_write_lpf( struct dsp_lpf *lpf, float *s );
+void dsp_read_lpf( struct dsp_lpf *lpf, float *s );
+void dsp_init_schroeder( struct dsp_schroeder *sch, float length, float gain );
+void dsp_process_schroeder( struct dsp_schroeder *sch,
+                            float *input, float *output );